Operational scrap problem

Dear Gurus

Suppose I have got 5 operations in a routing say

10 Stranding

11 Inner Sheath

12 Nylon Bond Sheath

13 Inspection

14 Batteening

If we make 1000 Meters on operation 10 we will not have 1000 meters when we get to last opn because of waste in each operation. So we have a waste factor, Stranding 6%, Inner Sheath 7%, Nylon Sheath 7%, and inspection 8%. (Battening is 0%) I put this scrap percentages in the routing as per the operations.

When I ran a production order suppose for 1000 pc the system is taking 1000pc as opertional qty in first operation but after that it goes on reducing the operational qty according to the scrap percentages that has been set in operations in routing.,.

My question is how can the system calculate the percentages and give the value 1000 in the last operation.That means in the first operation system should propose 1310pc . How can this happen ?

Regards

Sandip Sarkar